1. Field of the Invention
This invention relates to Group Transfer Polymerization of acrylates catalyzed by selected mercury compounds.
2. Background
U.S. Pat. Nos. 4,414,372; 4,417,034; 4,508,880; 4,524,196; 4,581,428; 4,588,795; and 4,605,716, and commonly assigned U.S. patent applications Ser. Nos. 627,919 filed July 5, 1984; 660,588 filed Oct. 18, 1984; 673,926 filed Nov. 21, 1984; 771,684, 771,685 and 771,686 filed Sept. 3, 1985; 786,101 filed Oct. 15, 1985; and 872,610 filed June 10, 1986; referred to hereinafter as "the aforesaid patents and patent applications", disclose processes for polymerizing an acrylic or maleimide monomer to a "living" polymer in the presence of an initiator, which is a tetracoordinate organosilicon, organotin or organogermanium compound having at least one initiating site, and a co-catalyst which is a source of fluoride, bifluoride, cyanide or azide ions or a suitable Lewis acid, Lewis base or selected oxyanion. Such polymerization processes have become known in the art as Group Transfer Polymerization (Webster et al., J. Am. Chem. Soc., 105: 5706 (1983)).
Preferred monomers for use in Group Transfer Polymerization are selected from acrylic and maleimide monomers of the formula CH.sub.2 .dbd.C(Y)X and ##STR1## and mixtures thereof, wherein:
X is --CN, --CH.dbd.CHC(O)X' or --C(O)X'; PA0 Y is --H, --CH.sub.3, --CN or --CO.sub.2 R, provided, however, when X is --CH.dbd.CHC(O)X', Y is --H or --CH.sub.3 ; PA0 X' is --OSi(R.sup.1).sub.3, --R, --OR or --NR'R"; PA0 each R.sup.1, independently, is a hydrocarbyl radical which is an aliphatic, alicyclic, aromatic or mixed aliphatic-aromatic radical containing up to 20 carbon atoms or --H, provided that at least one R.sup.1 group is not --H; PA0 R is: PA0 each of R' and R" is independently selected from C.sub.1-4 alkyl. PA0 Q' is [X"(R.sup.1).sub.q ].sub.3-x (R.sup.1).sub.x ; PA0 Q" is [X"(R.sup.1).sub.q ].sub.2-y (R.sup.1).sub.y ; PA0 each X", independently, is O, N or S; PA0 q is 1 or, when X" is N, 2; PA0 x is 0, 1 or 2; PA0 y is 0 or 1; PA0 R.sup.1 is as defined above for the monomer; PA0 Z is an activating substituent selected from the group consisting of --CN, ##STR2## --SR', --OP(NR'R").sub.2, --OP(OR.sup.1).sub.2, --OP[OSi(R.sup.1).sub.3 ].sub.2 and mixtures thereof; PA0 R', R", R and R.sup.1 are as defined above for the monomer; PA0 Z.sup.1 is ##STR3## X.sup.2 is --OSi(R.sup.1).sub.3, --R.sup.6, --OR.sup.6 or --NR'R"; R.sup.6 is PA0 R', R" and R.sup.1 are as defined above for the monomer; PA0 Z' is as defined above for the monomer; PA0 m is 2, 3 or 4; PA0 n is 3, 4 or 5; PA0 R.sup.2 and R.sup.3 taken together are ##STR4## provided Z is ##STR5## X.sup.2 and either R.sup.2 or R.sup.3 taken together are ##STR6## provided Z is ##STR7## and M is Si, Sn, or Ge., provided, however, when Z is ##STR8## M is Sn or Ge. PA0 X.sup.1 is ##STR10## provided, however, when the monomer is a nitrile, X.sup.1 is ##STR11## each R.sup.4, independently, is: (a) a C.sub.1-12 alkyl, C.sub.4-12 cycloalkyl, C.sub.6-12 aralkyl or di(C.sub.1-4 alkyl)amino group; PA0 each R.sup.5 is --CH.sub.2 CH.sub.2 -- or --CH.sub.2 CH.sub.2 -- containing one or more alkyl or other substituents that are unreactive under polymerizing conditions. PA0 L is I or ClO.sub.4 ; PA0 X' is --OSi(R.sup.1).sub.3, --R, --OR or --NR'R"; PA0 each R.sup.1, independently, is a hydrocarbyl radical which is an aliphatic, alicyclic, aromatic or mixed aliphatic-aromatic radical containing up to 20 carbon atoms or --H, provided that at least one R.sup.1 group is not --H; PA0 R is: PA0 each of R' and R" is independently selected from C.sub.1-4 alkyl; and PA0 R.sup.7 is a hydrocarbyl radical having 1 to 10 carbon atoms. PA0 Q' is [X"(R.sup.1).sub.q ].sub.3-x (R.sup.1).sub.x); PA0 Q" is [X"(R.sup.1).sub.q ].sub.2-y (R.sup.1).sub.y ; PA0 each X", independently, is O, N or S; PA0 q is 1 or, when X" is N, 2; PA0 x is 0, 1, 2 or 3; PA0 y is 0, 1 or 2; PA0 Z is --OC(X.sup.2).dbd.C(R.sup.2)(R.sup.3), ##STR12## or mixtures thereof; Z.sup.1 is --OC(X.sup.2).dbd.C(R.sup.2)(R.sup.3); PA0 X.sup.2 is --OSi(R.sup.1).sub.3, --R.sup.6, --OR.sup.6 or --NR'R"; PA0 each R.sup.1, independently, is a hydrocarbyl radical which is an aliphatic, alicyclic, aromatic or mixed aliphatic-aromatic radical containing up to 20 carbon atoms or --H, provided that at least one R.sup.1 group is not --H; PA0 R.sup.6 is: PA0 each of R.sup.2 and R.sup.3 is independently selected from H or a hydrocarbyl or polymeric radical defined as for R.sup.6 ; PA0 Z' is O or NR'; PA0 m is 2, 3 or 4; and PA0 each of R' and R" is independently selected from C.sub.1-4 alkyl.
(a) a hydrocarbyl radical which is an aliphatic, alicyclic, aromatic or mixed aliphatic-aromatic radical containing up to 20 carbon atoms; PA1 (b) a polymeric radical containing at least 20 carbon atoms; PA1 (c) a radical of (a) or (b) containing one or more ether oxygen atoms within aliphatic segments thereof; PA1 (d) a radical of (a), (b) or (c) containing one or more functional substituents that are unreactive under polymerizing conditions; or PA1 (e) a radical of (a), (b), (c) or (d) containing one or more reactive substituents of the formula --Z'(O)C--C(Y.sup.1).dbd.CH.sub.2 wherein Y.sup.1 is --H or --CH.sub.3 and Z' is O or NR' wherein R' is as defined below; and PA1 (a) a hydrocarbyl radical which is an aliphatic, alicyclic, aromatic or mixed aliphatic-aromatic radical containing up to 20 carbon atoms; PA1 (b) a polymeric radical containing at least 20 carbon atoms; PA1 (c) a radical of (a) or (b) containing one or more ether oxygen atoms within aliphatic segments thereof; PA1 (d) a radical of (a), (b) or (c) containing one or more functional substituents that are unreactive under polymerizing conditions; or PA1 (e) a radical of (a), (b), (c) or (d) containing one or more initiating sites; and each of R.sup.2 and R.sup.3 is independently selected from --H and hydrocarbyl, defined as for R.sup.6 above, subparagraphs (a) to (e); PA1 (b) a group of (a) wherein two or three of the alkyl, cycloalkyl and/or aralkyl groups are joined together by means of one or more carbon-carbon bonds; PA1 (c) a group of (a) or (b) wherein the alkyl, cycloalkyl and/or aralkyl groups contain within aliphatic segments thereof one or more hetero atoms selected from O, N and S; or PA1 (d) a group of (a), (b) or (c) wherein the alkyl, cycloalkyl and/or aralkyl groups contain one or more substituents that are unreactive under polymerizing conditions; and PA1 (a) a hydrocarbyl radical which is an aliphatic, alicyclic, aromatic or mixed aliphatic-aromatic radical containing up to 20 carbon atoms; PA1 (b) a polymeric radical containing at least 20 carbon atoms; PA1 (c) a radical of (a) or (b) containing one or more ether oxygen atoms within aliphatic segments thereof; PA1 (d) a radical of (a), (b) or (c) containing one or more functional substituents that are unreactive under polymerizing conditions; or PA1 (e) a radical of (a), (b), (c) or (d) containing one or more reactive substituents of the formula --Z'(O)C--CH.dbd.CH.sub.2 wherein Z' is O or NR'; and PA1 (a) a hydrocarbyl radical which is an aliphatic, alicyclic, aromatic or mixed aliphatic-aromatic radical containing up to 20 carbon atoms; PA1 (b) a polymeric radical containing at least 20 carbon atoms; PA1 (c) a radical of (a) or (b) containing one or more ether oxygen atoms within aliphatic segments thereof; PA1 (d) a radical of (a), (b) or (c) containing one or more functional substituents that are unreactive under polymerizing conditions; or PA1 (e) a radical of (a), (b), (c) or (d) containing one or more initiating sites;
Preferred initiators are selected from tetracoordinate organsilicon, organotin and organogermanium compounds of the formulas Q'MZ, Q"M(Z.sup.1).sub.2 and [Z.sup.1 (Q")M].sub.2 O
wherein:
Preferred co-catalysts are selected from a source of bifluoride ions HF.sub.2.sup.-, or a source of fluoride, cyanide or azide ions, or a source of oxyanions, said oxyanions being capable of forming a conjugate acid having a pKa (DMSO) of about 5 to about 24, preferably about 6 to about 21, more preferably 8 to 18, or a suitable Lewis acid, for example, zinc chloride, bromide or iodide, boron trifluoride, an alkylaluminum oxide or an alkylaluminum chloride, or a suitable Lewis base, for example, a Lewis base of the formula selected from (R.sup.4).sub.3 M' and ##STR9## wherein: M' is P or As;
Additional details regarding Group Transfer Polymerization can be obtained from the aforesaid patents and patent applications, the disclosures of which are hereby incorporated by reference.
Razuvaev et al., Vysokomol. Soedin. (B), 25(2): 122-125 (1983) disclose polymerization of methyl methacrylate and/or styrene initiated by a mixture of silicon tetrachloride and alkyls of mercury, tin or lead, at 20.degree.-50.degree. C. Sakurai et al., Tetrahedron Lett., 21: 2325-2328 (1980) disclose mercuric iodide catalyzed isomerization of (trimethylsilylmethyl)chloromethyl ketone to (1-chloromethyl ethenyl)oxytrimethylsilane.
Burlachenko et al., Zhur, Obschchei Khim., 43(8): 1724-1732 (1973) disclose isomerization of cis-ketene silyl acetals into the trans-isomer catalyzed by triethylsilyl bromide and mercuric bromide. Litvinova et al., abstract of Dokl. Akad. Nauk. SSSR, 173(3): 578-580 (1967); CA 67: 32720j, disclose the mercuric iodide-catalyzed rearrangement of triethylacetonylsilane to (isopropenyloxy)triethylsilane.
Baukov et al., abstract of Dokl. Akad. Nauk. SSSR, 157(1): 119-121 (1964); CA 61: 8333f, disclose the mercuric iodide-catalyzed rearrangement of (1-methoxy-1-ethenyloxy)triethylsilane to methyl 2-triethylsilylacetate.
Satchell et al., Qtr. Rev. Chem Soc., 25: 171 (1971) disclose that mercuric halides are very weakly acidic Lewis acids.
The present invention provides mercury containing catalysts which can be used in Group Transfer Polymerization of selected acrylic monomers. There is no suggestion in any of the foregoing references that such or similar mercury containing compounds would be useful as catalysts in Group Transfer Polymerization.